The Plain of Jars is a large group of historic cultural sites in Laos containing thousands of stone jars, which lie scattered throughout the Xieng Khouang plain in the Laotian Highlands at the northern end of the Annamese Cordillera, the principal mountain range of Indochina. In the context of the Vietnam War and the Secret War, the Plain of Jars typically refers to the entire Xieng Khouang plain rather than the cultural sites themselves.